Siemens S7-1200 System Manual page 598

Communication
10.5 S7 communication
Parameter
Connection name
Active connection
establishment
One-way
The GET/PUT icon in the Property View tree also changes from red to green.
Completed PROFINET S7 connection
In the "Network view", a two-way S7 connection is shown in the "Connections" table between
"PLC_1" and "PLC_3".
598
Definition
"Connection name" contains the default connection name (for example,
"S7_Connection_1"); control is enabled.
Checked and enabled to select the Local CPU as the active connection.
Read-only and unchecked.
Note: "PLC_1" (an S7-1200 CPU 1214CDC/DC/Rly) and "PLC_3" (an S7-300
CPU 319-3PN/DP) can both act as a server and a client in a PROFINET
GET/PUT connection, allowing a two-way connection.
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG